Remote fuse destruction device

ABSTRACT

The combination of a fuse and a means which is controllable from a distance, as by radio transmission and reception, to open a circuit by destroying the fuse.

United States Patent nu 3,575,681

[72] Inventor AlanSamuelNusbaum [56] References Cited Ph x. A z- UNITEDSTATES PATENTS 5; 9f:- f i 1969 3,161,131 12/1964 Kilmer 102/24 t d2,911,504 11/1959 Cohn 337/296 e a I 2,763,752 9/1956 Paet0w.... 337/182ss'gm Franklin 'z 1,966,466 7/1934 Smalley 337/182(x FOREIGN PATENTS943,070 5/1956 Germanyw, 337/185 54 REMOTE FUSE DESTRUCTlON DEVICE f f'i Gnheany 5 Claims, 3 Drawing Figs. Assistant Exammer-Dew1tt M. Morgan[52] U S Cl 337,! Attorney-Muellcr&A1chele 3 7 i [51] Int. Cl H0lh 85/00ABSTRACT: The combination of a fuse and a means which is [50] Field ofSearch 102/24; controllable from a distance, as by radio transmissionand 337/160, 182, 185, 296, l; 317/234 (4) 3 reception, to open acircuit by destroying the fuse.

ll ll REMOTE FUSE DESTRUCTION DEVICE BACKGROUND OF THE INVENTION Thepublic utility companies that supply electricity must from time to timeread meters in preparation of bills and when the customers service is tobe discontinued, the company must disconnect the electrical supply atthe customer's residence. One method of disconnecting the electricalsupply SUMMARY OF THE INVENTION In accordance with this invention anelectrical fuse is provided which has a thermal means mounted insufficiently close vicinity to the fuseable link portion of the fuse atthe customers residence as to melt the fuseablellink and thereby todestroy the fuse whereby the customers electrical service isdisconnected. The thermal means may include an electrical switch meanssuch as a silicon-controlled rectifier (hereinafter SCR) in series witha squib and may include exothermic materials, that is, materials whichproduce more heat when heated by the squib than the heat appliedthereto. Suitable means such as a coded receiving means, which may beany sort of a receiver including a radio receiver, may be provided toapply control potential to the SCR. If remote metering means areprovided to read this customers electrical meter, the remote meteringmeans may include controlling means to apply the control potential tothe SCR when the customer's service is to be disconnected.

BRIEF DESCRIPTION OF THE DRAWING The invention will be better understoodupon reading the following description in connection with theaccompanying drawing in which:

FIG. 1 is an elevational view of the fuse of this invention,

FIG. 2is an elevational view of the fuse of FIG. I viewed, however, at a90 angle from the view thereof. taken in FIG. I and FIG. 3 is adiagrammatic showing of an electrical circuit in which the fuse of FIGS.1 and 2 may be connected.

DESCRIPTION Referring to FIG. I, a fuse 8 which includes a fuse link 10is provided. This fuse link 10 may be a thin flat plate of fuseablematerial having a narrow necked down portion 12 about halfway betweenits ends 16 andl8. The central portion of the fuse link 10 may beincluded in a container 14. The bladelike ends 16 and 18 of the fuselink 10 may fit into contactors (not shown). When the fuse 8 is a mainfuse of a residence, all the current supplied to that residence flowsthrough the fuse, whereby removal of the fuse or its destructiondisconnects the residence from the electrical power supply. FIG. 2illustrates a means to destroy the fuse 8.

As shown in FIG. 2, spacers 20 and 22 are fixed to the link 10 atopposite sides of the neck portion 12 and a bridge means comprising aninsulation board 24 is fixed to the spacers 20 and 22, whereby the board24 is spaced from the link 10. An

SCR 26 is fixed to the board 24 on the side thereof towards the link I0,or the SCR 26 is deposited on a chip which is fixed to the board 24,anda squib 28 is fixed to the exposed side of the SCR 26. An exothermicmaterial 30, that is a material which produces heat when it is selfheated such as any easily combustible material, may be applied to thefree face of the squib 28.

The circuit for the SCR 26 and for the squib 28 of FIG. 2 is shown inFIG. 3. When the proper coded signal is sent to a coded receiver 32,which may be a radio receiver having an antenna 34, a control signal isapplied to thecontrol electrode of the SCR 26. The main electrodes ofthe SCR 26 are connected respectively to ground and to one terminal ofthe squib 28, whose other terminal is connected to any convenient pointof the electrical supply such as to the fuse link 10 at the location ofone of the spacers 22. When the receiver 32 applies a control voltage tothe control electrode of the SCR 26, current flows through the squib 28,causing it to become heated and causing the exothermical material 30 toignite, heating the fuse link I0 sufficiently so that the necked downportion 12 of the fuse link 10 will melt, opening the main fuse 8 of theresidence and thereby disconnecting the customers electrical service.

If the heat produced by the squib 28 is itself sufficient to melt thenecked down portion 12 of the fuse link 10, then the exothermic material30 may be omitted. It is noted that the SCR 26, the squib 28 and theexothermic material 30 are all located within the container 14 and thatthe connections to one of the main electrodes of the SCR 26 and theconnection to the control electrode of the SCR 26 are taken out of thecontainer 14 at any convenient location.

Iclaim:

I. A fuse comprising:

a fuse link having a meltable portion,

support means fixed to said link and extending in the vicinity of saidmeltable portion,

a semiconductor switch having two main electrodes and mounted on saidsupport means and having one main electrode connected to said link atone side of said meltable portion,

an electrically controlled heat producing means having a terminalmounted on said support means and facing said meltable portion, and

the other main electrode of said semiconductor switch being connected toa terminal of said electrically controlled heat producing means.

2. A fuse comprising:

a fuse link having a meltable portion,

a bridge means bridging said meltable portion,

a silicon-controlled rectifier mounted on said bridge portion and havinga main electrode connected to said link at one side of said meltableportion,

a squib mounted on said bridge and facing said meltable portion, and

the other main electrode of the said silicon-controlled rectifier beingconnected to a terminal of said squib.

3. The invention as expressed in claim 2 in which said meltable portion,said bridge means and said siliconcontrolled rectifier are mounted in asingle container.

4. The invention as expressed in claim 3 in which an exothermic materialis provided in contact with said squib and also in said container.

5. The invention as expressed in claim 3 in which a connection to theother terminal of the squib and the connection to the other mainelectrode of said siliconcontrolled rectifier extends through saidcontainer.

1. A fuse comprising: a fuse link having a meltable portion, supportmeans fixed to said link and extending in the vicinity of said meltableportion, a semiconductor switch having two main electrodes and mountedon said support means and having one main electrode connected to saidlink at one side of said meltable portion, an electrically controlledheat producing means having a terminal mounted on said support means andfacing said meltable portion, and the other main electrode of saidsemiconductor switch being connected to a terminal of said electricallycontrolled heat producing means.
 2. A fuse comprising: a fuse linkhaving a meltable portion, a bridge means bridging said meltableportion, a silicon-controlled rectifier mounted on said bridge portionand having a main electrode connected to said link at one side of saidmeltable portion, a squib mounted on said bridge and facing saidmeltable portion, and the other main electrode of the saidsilicon-controlled rectifier being connected to a terminal of saidsquib.
 3. The invention as expressed in claim 2 in which said meltableportion, said bridge means and said silicon-controlled rectifier aremounted in a single container.
 4. The invention as expressed in claim 3in which an exothermic material is provided in contact with said squiband also in said container.
 5. The invention as expressed in claim 3 inwhich a connection to the other terminal of the squib and the connectionto the other main electrode of said silicon-controlled rectifier extendsthrough said container.